Wow, I guess I must be the lucky one. Now, Yahoo! Maps, that I've had problems with. On our last anniversary, we decided to go to Gasho, a Japanese restaurant where they cook the food on the table in front of you (how neat!). My in laws (where we were staying @ the time, since they were watching the kids) gave us printed directions via Yahoo! Maps, and they added a ton of stuff, and it was completely confusing.
MapQuest? Five lines of directions, leading right to where I wanted to go.
I'm not saying they're infallible (obvously a 300 mile stint in the wrong direction is very, very bad) but I've never had an issue. And I always check it before I set off.
I bought the AAA Trip Planner some years back. @ the time I was living in Monticello, NY and wanted directions to the Bronx. It was just over 100 miles away. When it outputted the results, it told me the final miles were nearly 400! Then I looked at the map. For whatever reason, the stupid software thought the Bronx was in Buffalo.